Pressure and temperature relief valve and diaphragm valve

Abstract

A temperature and pressure responsive relief valve assembly preferably used in the cooling system of an internal combustion engine to control the rate of flow of a coolant fluid through the engine, which valve assembly comprises a housing having an inlet and an outlet, and a fluid passageway interconnecting the inlet and the outlet and including a valve seat, a pressure responsive diaphragm valve in the passageway and including a peripheral edge fixed to the housing and an annular combination valve member and valve seat defining an opening and forming a portion of the passageway and movable relative to the valve seat and movable toward the outlet in response to fluid pressure the inlet, a thermostat mounted in the passageway and including a valve member movable in response to operation of the thermostat, and a spring in the passageway for biasing the combination valve member and valve seat into a seated position on the valve seat and on the valve member, and a second spring for biasing the valve member into a seated position on the combination valve member and valve seat.

I claim: 
     
       1. A temperature and pressure responsive relief valve assembly comprising a housing including an inlet and an outlet, and a fluid passageway in said housing interconnecting said inlet and said outlet and including a valve stop, a pressure responsive flexible member in said passageway and including a peripheral edge fixed to said housing and an annular combination first valve member and valve seat defining an opening forming a portion of said passageway and being movable relative to said valve stop, a thermally responsive assembly movably mounted in said passageway and including a thermally responsive actuator and a second valve member movable in response to operation of said actuator and relative to said combined first valve member and valve seat for seating engagement between said second valve member and said combined first valve member and valve seat, and means in said passageway for biasing said combined first valve member and valve seat into engaged position on said valve stop and on said second valve member. 
     
     
       2. A relief valve assembly as set fourth in claim 1, wherein said combined first valve member and valve seat is made of non-metallic material. 
     
     
       3. A relief valve assembly as set forth in claim 2, wherein said flexible member comprises a diaphragm and wherein said thermally responsive actuator extends through said opening. 
     
     
       4. A relief valve assembly as forth in claim 3, wherein said combined first valve member and valve seat is integral with said flexible member. 
     
     
       5. A relief valve assembly as set forth in claim 1, wherein said flexible member is made of a non-metallic material. 
     
     
       6. A relief valve assembly as set forth in claim 1, wherein said housing includes a top portion and another portion and means for removably fastening said top portion to said other portion of said housing. 
     
     
       7. A relief valve assembly as set forth in claim 1, wherein said flexible member has therein an orifice. 
     
     
       8. A relief valve assembly as set forth in claim 1, and further comprising means in said passageway for biasing said second valve member into a seated position on said combined first valve member and valve set. 
     
     
       9. A relief valve assembly as set forth in claim 8, wherein said means for biasing said second valve member has greater relative strength than said means for biasing said combined first valve member and valve seat. 
     
     
       10. A diaphragm valve for use in a pressure relief valve assembly including a housing having an inlet and an outlet, and a fluid passageway in the housing interconnecting the inlet and the outlet and including an outer valve stop, and an inner valve seat mounted in the passageway, said diaphragm valve comprising a flexible diaphragm adapted to be located within the passageway and including a peripheral edge adapted to be fixed to the housing, and an annular valve member on said flexible diaphragm and defining an opening forming a portion of the passageway and being movable relative to said outer valve stop and to said inner valve seat for seating engagement therewith. 
     
     
       11. A diaphragm valve as set forth in claim 10, wherein said diaphragm valve includes an integral valve member. 
     
     
       12. A diaphragm valve as set forth in claim 10 wherein said valve member is made of a non-metallic material. 
     
     
       13. A diaphragm valve as set forth in claim 10, wherein said valve member has therein an orifice. 
     
     
       14. A diaphragm valve as set forth in claim 10, wherein said inner valve seat is movable relative to said valve member and to said outer valve stop in response to changes in the temperature of fluid in said passageway. 
     
     
       15. A diaphragm valve as set forth in claim 14 and further comprising member for biasing said valve member toward said outer valve stop and said inner valve seat, and means for biasing said inner valve seat toward said valve member. 
     
     
       16. A temperature and pressure responsive relief valve assembly comprising a housing including an inlet and an outlet, and a fluid passageway in said housing interconnecting said inlet and said outlet and including a valve stop, a pressure responsive flexible member in said passageway and including a peripheral edge fixed to said housing and an annular combination first valve member and valve seat defining an opening forming a portion of said passageway and being movable relative to said valve stop, a thermally responsive assembly movably mounted in said passageway and including a thermally responsive actuator extending through said opening and a second valve member movable in response to operation of said actuator and relative to said combined first valve member and valve seat for seating engagement between said second valve member and said combined first valve member and valve seat, means in said passageway for biasing said combined first valve member and valve seat into engaged position on said valve stop and on said second valve member, and means in said passageway for biasing said second valve member into a seated position on said combined first valve member and valve seat. 
     
     
       17. A relief valve assembly as set forth in claim 16, wherein said means for biasing said second valve member has greater relative strength than said means for biasing said combined first valve member and valve seat. 
     
     
       18. A relief valve assembly as set forth in claim 16, wherein said combined first valve member and valve seat is integral with said flexible member.